Cam-generating machine



Aug. 31 1926.

V L. E. TOPHAM CAM GENERATING momma Filed Nov. 12. 1921 4 Sheets-Sheet 1 Aug. 31 1926. 1,597,741

E. TOPHAM CAM GENERATI NG MACHINE Filed Nov. 12, 1921 4 Sheets-Sheet 5 a a 7 AM Aug. 31, 1926. 1,597,741

| E. TOPHAM CAM GENERATING MACHINE Filed Nov. 12 1921 4 Shoots-Sheet 4 it, so that the feeding has all to be done at.

present disclosure is mama Aug. 31, 1926.

UNITED STATES PATENT oFFl-cs;

remit, or m, assren'oa mm seen u- '2 conroaa'rron, or BALM a eoarona'rros or east-ammo A li ation ma was, 1:; m1. maize. new,

' inventionrelates to methods of cutting cams and to cam" cuttingmachines. Cams are generally cuton a copying lathe, which the model can or pattern and the work piece are mounted to rotate a model wheel or guide and tool tively',- the relative position of tool an work being governed by the continuous contact of the model and model wheel. The model according to this practice, is made by hand and is exceedingly expensive.

A peculiar cam generating problemhas arisen in connection with an automatic side lasting machine invented by R. H. Lawson and described and claimed in his application Ser. No. 539,280, filed Feb. 25, 1922,"and

a later development of which, involving the cam in question, is described and claimed his application Ser. No. 687,749 filed May 9, 1923, the present invention s disclosed in connection with a machine for genera the cams for this machine. It shoul be understood however, that the illustrative. only, and that it is not to be understood as limiting certain broad features of the invention. In the side lasting machine mentioned,

the shoe is mounted on a jack, which is auto maticall moved to carry theshoe past sewing mechanism. It is necessary that the shoe remain motionless while a needle is in the time when the needle is not in en'ga ment with the shoe. The critical or locating points on the continuously moving jack cam are accordingly all dwells, of course. of finite and substantial extent, and the problem, therefore, as applied to this particular type of machine, is to locate these dwells accurately and to get from one to'the next without Jar, it being otherwise immaterial just what shape the cam is between'the dwells. Inasmuch as a different system of cam dwells is required for every difierent style of last, the model making under heretofore existing practice involves at expense.

In view of these and similar conditions it is an important object of the present invention to rovide for generating for example, a cam aving such peculiar c aracteristics,

greater simplicity 'or ease, and at much smaller e than is possibleunder'the practice existing prior to the'present invention. To this end Icontemplate' a pattern only single points corre-v sponding to t e several cam dwells seen-- rately positioned, and using only these points in the generation-of the several corresponding dwells. These {points on this pattern arejoined b curves of substantially optional form whic arepreferably of substantially even rise or fall as the case may be for example, Archimede'an spirals or circles which closely approximate them) and which are used to generate, the transition parts of the cam between dwells. This methodof cam eneration, in its several aspects, which will made clear asthe description proceeds, constitutes'an important part of the invention; It is clear that since only the isolated dwell points of the model need to be accuratel plotted, and since, as be shown, t 0 com oundings oken of can be done mechanica y, the making of the model is an extremely economical matter.

As herein exemplified, in another important aspect the invention resides in compounding with the above-mentioned curves,

on the model or' pattern) of even rise and all curves of easy starting and stopping characteristics incident to' the generation of the transition portions of thecam. I contemplate the mechanical com ounding with a curve of a simple nature or the sake of easy mechanical generation) as, for example, a straight line, circle, or curve of substantiall uniform rise or fall, onthe model, a curve liaving arbitrary characteristics as those of easy starting and stopping. Considering the invention in its machine aspect, in the illustrated embodiment. of the invention I have advantageously effected both of the objects just discussedv by providi a control between the model and work river (assuming, for example, that we are dealing with that form of pattern reproducin machine in which the model wheel an tool are fixed and the model and work move over them), which holds the model motionless on its dwell points, and

then, effects a rotation over the following curve which modifies that curve in the way desired. This is secured by an irregular angular velocity ratio between the model and work which relatively displaces the model points around the work so that the slope of the curve joining them is changed. 01', still more broadly stated, points equally spaced around the cam do not correspond to points squall spaced around the model, the 'term equa ly being broad enough to mean here that the model points are not spaced equally to the corresponding cam points, nor necessarily even spaced equally among themselves, and vice versa. e method of cam generation im lied in what has just preceded and the mac anioal means for practicing it constitute very nnportant aspects of the invention. In the illustrated machine for racticing the methods just discussed, whic itself also is an important part of the invention, I have provided means for driving the work and a worm wheel and worm for driving the attern. The worm is a. sliding worm w ich moves tan entially along its motionless worm wheei durin the cutting of the dwell, and then moves ack, driving the wheel with it, during the generation of the transition portion. This is conveniently accomplished by a ath cam running around the worm body, having the same lead as the worm over the dwell cutting part of the circuit, and a portion connecting the ends of the equal-lead part, properly designed to produce the easy starting and stopping feature on the cam on the transition part of the cut.

In another aspect, the invention contemplates broadly the reproduction of a pattern y moving the pattern and work at dilferent speeds past their respectively cooperating model wheel and tool. In one way of looking at the matter, this is effected by the sliding worm feature discussed above. om another point of view, however, it involves something quite diil'erent. It is of course desirable, for reasons of economy, to use the same sliding worm in the machine. So far, then, there would always be a correspondence, between definite sectors on the model and definite sectors on the work. There would be relative peripheral irre larities between the model and work wit in these sectors, but the sectors themselves would always correspond, that is, the model wheel and cutter would always be at their end points at the same time, respectively. Under some conditions, there is an advanta in varying this condition, so that a mofi sector corresponding to a work sector can be made longer or shorter in order to secure greater sensitiveness and accuracy in the cutting on the model. In this aspect of the novel method of cam cutting herein disclosed, the desireu result is practically accomplished by a stem of ange g between the mode and work so that, for example, a sector on the work can be made to correspond to a sector of difierent magtiona form joining a set of accurate y located dwell or otherwise critical points in order. Advantageously I have provideda face plate having angular-1y spacedradial guides in it in which pinsor bushings or the like can be accurate y 'tioned to correspond to the carefully ocated dwell or critical points, in connection with which pins can be secured interchangeable curved guides to connect the points. These guides are furnished in a variety of "shapes so that the shape best adapted to that articular locality of the cam may be selec It will be understood that while I have disclosed the invention in connection with a machine for cutting revolving cams, the invention is not to be understood as so limited except so far as pointed out in the claims. The invention in many aspects is applicable to the production of cams which have a translatory as distinguished from a rotary movement.

The invention in these and other aspects will be better understood from the fo owing description taken in connection with the drawings, which show an embodiment selected for illustrative purposes.

Fig. 1 is a diagram illustrating the pattern, the cam and the method of generation of the latter;

Fig. 2 is a development of the cam which efi'ects the sliding of the worm;

Fig. 3 is a side elevation of the machine, the pattern B and the work piece C, which are on the side toward the observer, being removed to facilitate the disclosure of the parts behind them;

Fig. 4 is a section on line 44 of Fig. 3

Fig. 5 is a plan; V

Fig. 6 is a development similar to Fig. 2 but in another position;

Fig. 7 is an elevation of a. universal model;

Fig. 8 is a section on the line 88 of Fig. 9 is a detail of the other side of the mechanism shown in Fl 7;

Fig. 10 is a detail of the sliding worm construction.

The side lasting machine of application 'wnsintheeh Fig.4) of application Ser.

theshoe. Thecamueed numbered-1 0. 687,10) to conti-ol tbejack eves aflat disk havrngflte csm surtace on rte periphery.

wes assigned 89 of the uftheccsnwastogettherates? a? it "r. m o c urmg w y a'nd then to move tiom The eleven of the cam and the were used to return the jack to in sition. Theimprotsntpartsofthecam tlm'eforethefll or%cvcle dw ellawh1 hold the jack uring e st:

to the next cles used 85 61' onl thlng required of us. other wa thatth movethejackto position wi jar, otherwise immaterial.

The master cam or geattern for the cam cutting machine may developed as lows. The dwell points are accurately cated every 82 around the pattern by any convenient method. way is to putalastintothe "candturnthe machine and move the jack hand, marking the critical positions the can on e blank. About half of thepattem is shown in Fig. 1. The center 0 the patternflilzatA. nmlweu rgglntfl lgflg a on pattern p e. pom etc. are plotted onfthe diwin asthin the corresponding p051 10118 en y e centerof the camroll. The model wheel also uently desi sted as follower, model guie,"orlea ,uscdinthem his machine is shown-at (see an of the positions 10-4, etc., in Fig. 1). t, is an importent object of the accent invention to use these plotted .poin corresponding to 1, 2, 8, etc. to generate the dwells of the cam, preferably with no movement between the model wheel and pattern during the dwell generation, using the movement of the model wheel between the points 1, 2 3 etc., solely to generate the transitional scyclesoftheeem sincethese /gcyeles do not have to satls any rigid conditions, the pattern outline can the $3 1, 2,B etc.,canbefilledininanyd convenrent way. The ideal path between two consecutive points is a P1006 ofan modem iral, but th s is more expensive to producet anthesim lercrrculararewhich was adopted and w ioh furnishes a close approximation to a path of'nniform rise or fall r d around the cam.

ttem is then aid on a rotary circular tale with two consecutive plotted polnte on the circumference of the table, and a circular are milled from one to the other.

course, drawn h roll observer in 8 otted to rotate w1 I spaced by e co ar 28 which is so at the are not tigh 'lhesearcsereehowninF' .1,inconncction with the successive wheel tions. The are all lettered B with mm indicating is critical points to which they belong, as 8-2-8 the are H v to the points and mthe'lhesq arcs arable model wheel so that its center can fall on thepoints -2,etc.,asshpwninF' 1. The centersoft arcsaresnn lyma 1-8, 3-4, etc. The circle 12 we about the point A or center shows how the cam rises and falls. The pattern is thus generated at veqyhsmnll expense.

1mm thus generated is m the shownin Figs. 8', 4 and 6. The base 14 is equip with a l'lb or old, which the 17 of the m s can ll sl gbackandfo being ulledmone direction by the weight 18. body has n bearing m which is mounted s. hollow shaft 20, on one end of which is mounted the attern B, in any convenient way. This she is driven by a worm wheel 22.

Mounted inside the hollow shaft is a see and shaft 24, having a worm wheel 96 and an an tsir-[yl graduated ptllahtg fl'lflllmyed on oneen 1e attercoopera' wi a intor or index 21" mounted on the train: 17. On the other end of the-shaft toward the though not 5 own there in order to disclose the other mechanism more clearly) is mounted the work iece O it The ettern an work piece s l l ped srran t y c am togeth e so that the shafts and 24 can retate independently.

Mounted in the body 17 is the main drlve shaft 29, having a hand wheel 30, a ulley 81, a worm 89 to drive the worm w 26 end a splined pinion 38 meshing with an idler pinion 84, on an arm ivotally mounted on a shaft 86 mounts in the frame 17. The spline permits ready disengngement of the pinious 88 and 34. A twoermed bell crank 37 is also pivotolly mounted on the shaft 86, and one of its arms is clamped by a slot and bolt at B8. The other arm of the bell crank 37 carries pinions 89, lac-{ed together, engaging respectivcly the i er pinion 34 and a. gear 41, fast on the shaft 86. The ohan described will secure any desi direction and speed relation between the shafts 29 and Arch 6. The shaft 36 also carries a. 1011 pinion 44. The shaft 29 will thus drive t e shaft aspects. InJhe meohi e the If a'77 boothed 89-were the work woilld :evo Y6 77 for every 82 .of =tho'model The-dwell art or the. qleoqi be J R -e w 2 l n -l I 4 center of'the my model in whole mints. Fl- 1 '1 e, 923% s set of model e m einbod trait-Poi the ptesentjn vfinfiqn, andwh i e fhas proved 'aimple and oohvenient as ahownin' moun curve onlth'e m poipta moved -ir- (moles eboot. the

ma closed Ills op n. has.

preotice the invention in its broadestin AIM tgyq machine woul p l be.

the purpoqea of the partiouler'lnwsofi prob I and 8101310 would come 8";

" is from-the.

"t t. T tthiadi m mersoc o mee e a 8101:90, bquilfledby-two radiijns odof' WO ngue impeotiv ely the oof th a do! goars'm aefoll'owe: lem dumbed, and slots 72, are err! 83 hue 881M611, I may between qdjment mum e 80 has'82 teeoh. slots -79 are oounbermnk is shown at!!! 'to, I #QO hes'82 teeth. receive bushing: 76 aha-pod to fit-theoofinber A #41 has 121 .teeth mink portions and mieotingout, throng: '10- #44 has lfi'teeth; thebptokof the p is shown in Fig. 51 has Theee bu Ire threaded for nuts 78, I #2211 11: 45 teeth. A gage pin 0 when phoedfin a. .lo #26 h '127 aewes toedjust its distanoe '-from the oen- #48 has 4 threads. fry hub. .82 by e mjoro lneterl After dim. ll #32 has 1 thread. ment it ie by.the nut 78 and 4 he win ifm the 22 e mifi m fifififilfifi filfi u was ado ma beoeuso it ain l lifledzthe treati F lm-8, 9. wee-mum ment 0' the Lawson pro em. Thtm one 81 6 of 8 Fqu'ghmdha' pilots 186.04:

tum of the worm 48. causes dirooflfiae 83 he gq sof A118 bofitonymet M -th6pins him' of the model." ,The gear patio .1s mo nted o 'hyo :adjaoe'n adjusted the-shaft 29 ml the"werm wheel 22is an #3 O V]. --0 6 g 33'X32X1-5 X4 e is of theimodel-wheel. w j 10. The'lgqdimof thojaegment igboohoeen whieh is the Mo the shift, 29 1 pgzde oshmflrthe (mm 82) m1 the worn; wheel 20. (The p d-iqmngfi m 13.0- m r'fllis shown muchtooemallinthedrewto pass through any-one d int o fmg,for the'aake of oleamesezfi; It is pla nned 2 13 9 W9 n M w @0111 the ob g wi, fll' 'gm a fl r w mmtmhvbe a It i Pmt e ti f th r e desired by the 0110106 oi the aogmentpf the ryelogi f thgj h l 22 1 a proper gadms, and thus the cam int cola cyco or'tum o thesheit 4e of o. mspq m g to t reh w wheel'26 7v inversely with the num-. mp w d om center; mo m berofteo in" j pqnm g t naus up a h pm undhmg'gi' o two in henna aniveted- 393mm 313??? is: fe M 01 .d ted th v6 82'orev"32" 0 am v ewo one-"0 e o m-- e W m :speciflo problem discosseithe Aspects the oonstruoted as follows The feoe-nlat'e would be divided inhn mun] camsles illustreted in 5, as well we desire with the spiral.

'canbe set up -wheel 89, and turn ofi meme.

p such as 80 sectors, for example, and ing cnrve on the work piece from a curve the ratio between the 1 48 and 22 would of fi te length on the pattern correspond, as t'thre 48 teeth, for the it That rovement 1n the of cum same exam 1e. Thus the model cycle is 80 generation which consists in mounting a patlo and e-model turns 80 for every torn and a work piece in a pattern copying of e shaft 48 A sp impelled stop in machmennd mo them relatrvely to the (Fi 8 and 10) incorpo in model wheel andetoolat d fl'erent so the macfine tostop the shaft at the exact that the correspond ng arts of the pattern end ofeach revolution. The change gearing and work vary m angular extent. would also be made as before, so that-a 4. 1m rovementin the art ofcam wheel 89 had a number of teethequsltothe generation w chponmsts in plac ng a pat.- number of de turned by the wheel26 torn and work piece in a pattern copying during a mode cycle. Suppose now that we machine, and rotatu? them relative! to the wish to cut acam having in succession along model wheel and respectively, e rota 'itsedge a. dro over 27, a dwell over 84", on of one of said ob ects being mterm ta drop over a dwell over-13 etc. We nk will set up these drops in succession in sucm' the art of cum cessive 80 iltigirvals arountdhthg falrigpl i ntfi as w oons1sts .in providitfigtha abovedescri 'o e we esei avmgpo onsoorrespon e als g in t h e iace plate, ntgit critical points aceuratelynplotted, an oined is not nry).. We nt'in a 27 toothed by curves of substentm v constan se or the first drop in the the transition curves fall, and genera drop-in the first 27 of the work,'untilthe points of the cam by between the criti 'sto inzialla the a mxlmate Archimedean mm a curve of I and ap on thd mode modified by the. s pp gc rwt nstm upon th an curves 64-456 adopted to com und anything -"of.nse onfallme inion 33 6., That in the art of cm then pulled out of the train, and the rotation --goneratlon ;w ,ch, .m providing of the work continued over 84 from the 27 ode hnv 1ng portions correspon the to the 61 point as measuredon thefl'plate 27. critical P mtB accurately plotted, an lomed The 33 is then replaced ine train. y rves of snbstantially constant rise r (A slight turn of the shaft 29 may rhape djg pratmg the transition curves beli h thi -w 11 tween the critical mts of the cam by longie dwell y less th tudinall relative y displa the points 'of the fcurves of rise 0rd all) to procdliioe cnrveso easy starting an pping r- 7. That im rovement in the m of cam be necessary to accom afiect the length of half of (If this error is prohibitive the spline drive generation or 'ch consists in providing a of the gear 83 may be changed to a c1 model of approximately uni- A 26 toothed gear 39 is inserted 8113 516 form curvature andsuperposing upon said second drop, set up in the second 30 of'the curves in the reproduction a curve having model, is turned off on the 6187 interval certain redetermined" characteristics not of the work. The r 88 isthen ulled out embodi v in the model whereby the said and the next dwe turned 05, .1 :v ajpearin the'work. an cam whatever can be'cut'by the machine. 8. In a machine 0 the class described,

e machine will ordinarily'be model wheel and a model holder" the hand wheel 30, especiallywhen the stop pin 104 is used. Having described my invention,

a r a tool, and a holder, me, in for edwsm mative traverses between'the members of each what I of said pair of instrumentalities, and a claim as new and desire to secure by Letters variable motion mechanism between the two Patent of the-United States is:-- airs whereby one rel'ative' traverse may be 1. That im rovement in the art of-cam interrupted while the other proceeds. generation w 'ch consists in roviding a 9. In a machine of the class described, a pattern having occur-stair :5 plotte points cormodel wheel and tool, a model holder and responding to the dw of the cam to be work holder, and m for eflecting formed, said points be' connected relative movement of the model whee curves, generating the dwe on the wor' around the model holder and of the tool piece irom the points, and generating the around the work, said movements having a transition curves of the cam between the variable ratio of angular velocitim. dwells from the curves on the pattern. 10. In' a machine of the class described, a 2. That im rovement in the art of cam model wheel and tool, amodel holder and eration w 'ch consists in -%nerating a work holder, and for oil curve of finite length on the wor iece from relative movement of the model wh a single point of the pattern, an a followaround the model holder and of the tool around the work, one of said movements being intermittent, but of the same average angular velocit as the other.

11. In a mac ine of the class described, a model wheel and tool, a model holder and work holder, and mechanism for efi'ectigleg relative movement of the model wh around the model holder and of the tool around the work, one of said movements being intermittent.

12. In a machine of the class described, a model wheel and tool, a model holder and work holder, and mechanism for efiectin relative movement of the model whee around the model holder and of the tool around the work, one of said movements being discontinuous.

13. In a machine of the class described a model wheel and tool, a model holder and work holder, and mechanism for eifectin relative movement of the model whee around the model holder and of the tool around the work, said movements having different (but the same average) angular velocities.

14. In a machine of the class described, a model wheel and tool, a model holder and work holder, and mechanism for effecting relative movement of the model whee around the model holder and of the tool around the work, said movements occurring in cycles, and the an lar velocity of the first said movement difiering from that of the second in every cycle.

15. In a machine of the class described, a model Wheel and tool, a model holder and work holder, and mechanism for effecting relative movement of the model whee around the model holder and of the tool around the work, comprising a prime mover, and drives connected thereto for effecting the two said movements, one of said drives having an intermittent motion mechanism to alter its relation to the movement of the prime mover.

16. In a machine of the class described, a

model wheel and tool, a model holder and work holder, and mechanism for efiectin relative movement of the model whee around the model holder and of the tool around the work, comprising a prime mover, and drives connect thereto for efi'ecting the two said movements, one of said drives having an automatic variable motion mechanism to alter its relation to the movement of the prime mover.

17. In a machine of the class described, four primary instrumentalities, viz, a model wheel and tool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in pairs, comprising a prime mover, a drive between the prime mover and an instrumentality of each pair, one of said drives oomtality of eac prisin a worm wheel and sliding worm to vary t e uniformity of the drive.

18. In a machine of the class described, four primary instrumentalities, viz, a model wheel and tool a model holder and work holder and mechanism for eifecting relative traverses between said instrumentalities in airs, comprising a prime mover, a drive tween the rime mover and an instrumentality of eac pair and a device for augmenti and retar ing the action of one of said drives in timed relation to the other.

19. In a machine of the class described, four primary instrumentalities, viz, a model whee and tool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in airs, comprising a prime mover, a drive etween the prime mover and an instrumenpair, one of said drives comprising a worm and worm wheel, and means for moving said worm in the direction of its axis to vary the speed of the drive.

20. In a machine of the class described, four primary instrumentalities, viz, a model wheel and tool, a model holder and work holder and mechanism for eifecting relative traverses between said instrumentalities in pairs, comprising a prime mover, a drive between the prime mover and an instrumentality of sec pair, one of said drives comprising a worm and worm wheel, and means for moving said worm in the direction of its axis in timed relation to the other drive to var the speed of the drive.

21. n a machine of the class described, four primary instrumentalities, viz, a model whee and tool, a. model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in pairs, comprising a prime mover, a drive between the prime mover and an instrumen= tality of each pair, one of said drives comprising a worm wheel and sliding worm to vary t e uniformity of the drive, and a cam for sliding said worm in the direction of its axis.

22. In a machine of the class described, four primary instrumentalities, viz, a model wheel and tool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in pairs, comprising a prime mover, a drive etween the rime mover and an instrumentality of eacli pair, one of said drives comprising a worm constructed and arranged to slide in the direction of its axis, and a cam constructed and arran d to slide the worm during a certain revo ution b an amount erpial to its lead during suc revolution, w iereb the corresponding drive may be stoppe during the activity of the cam.

23. In a machine of the class described, four primary instrumentalities, viz, a model wheel and tool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in pairs, comprising a prime mover, a drive between the riine mover and an instrumentality of e'ac 1 pair, one of said drives com prisin a worm constructed and arranged to slide in the direction of its axis, a cam mounted on the worm, and an element engagin the cam to slide the worm.

24. n a machine of the class described, four rimary instrumentalities, viz, a model whee and tool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in airs, comprising a prime mover, a drive tween the rime mover and an instrumentality of one pair, one of said drives comprising a worm constructed and arranged to slide in the direction of its axis, a spiralcam mounted on the worm body and having a lead equal to that of the worm, and a cam roll mounted on the frame of the machine to cooperate with the cam.

25. In a machine of the class described, four rimary instrumentalities, viz, a model wheel andtool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in pairs, comprising a prime mover, a drive between the prime mover and an instrumentality of each pair, one of said drives com prising aworm constructed and arranged to slide in the direction of its axis, a spiral cam mounted on the worm body and having a portion with a lead equal to that of the worm and a return ortion connecting the ends of the said equa -lead portion whereby the worm may drive its worm wheel intermittently at normal average velocity.

26. In a machine of the class described, four rimary instrumentalities, viz, a model whee and tool, a model holder and work holder and mechanism for effecting relative traverses between said instrumentalities in airs, comprising a prime mover, a drive between the prime mover and an instrumentality of each pair, said drives being arranged to transmit the same average velocity to their driven instrumentalities, one drive comprising a worm arranged to move in the direction of its axis to vary the uniformit of its drive.

27. cam generating machine comprising a model wheel and a model having isolated points plotted on it corresponding to the dwells oftthe cam, and curves of substan tially constant rise or fall connecting the said points in order, a tool and a work holder, means for driving the work holder, means for driving the model in timed relation to the work holder and a device for holding the model wheel on a said point of the model while a corresponding dwell is cut on a work piece held by the work holder.

28. A cam enerating machine comprisin a model whee and a model having isolat points plotted on it corresponding to the dwells of the cam, and curves of substantially constant rise or fall connecting the said points in order, a tool and a work holder,

means for driving the work holder, means for drivin the model in timed relation to the work older, 0. device for holding the model wheel on a said point of the model while a dwell is cut on a work piece held by the work holder, and means for comdpounding' with the movement due to the sai curves a modifying movement to shape transition curves between dwells on the work piece.

29. A cam generating machine comprisin a model wheel and a model having isolate points plotted on it corresponding to the dwells of the cam, and curves of substantially constant rise or fall connecting the said points in order, a tool and a work holder,

means for driving the work holder, means for drivin the model in timed relation to the work older, a device for holding the model wheel on a said point of the model while a dwell is cut on a work piece held in the work holder, and means for feeding the said curves of substantially constant rise or fall over the model wheel at a non'uniform speed to shape transition curves of predetermined characteristics between dwells on the work piece.

30. A cam generating machine-comprisin a model whee and a model having isolate points plotted on it corresponding to the dwells of the cam, and curves of substantially constant rise or fall connecting the said points in order, atool and a work holder, means for driving the work holder, means for drivin the work older, 9. device for holding the model wheel on a said point of the model while a dwell is cut on a work piece held in the work holder, said means comprising a worm arranged to move parallel to its axis while rotating, and a cam arranged'on the worm body and having a lead equal to the worm-lead to efi'ect said movement.

31. A cam generating machine comprising a model wheel and a model having isolated points plotted on it corresponding to the dwells of the cam, and curves of substantially constant rise or fall connecting the said points in order, a tool and a work holder, means for driving the work holder, means for driving the model in timed relation to the work holder, :1. device for holding the model wheel on a said point of the model while a dwell is cut on a work piece held in the work holder, said means comprising a worm arranged to move parallel to its axis while rotating, a cam arranged on the worm body and having a lead equal to the wormlead, to effect said movement, and a second cam connected and arranged to compound the model in timed relation to.

a non-uniform axial movement in the opposite direction with the rotary movement of the worm.

32. A cam generatin machine having a model wheel, tool, m el holder and work holder, means for effecting relative traverses between the said four instrumentalities in pairs whereby a model contour may guide the tool and mechanism for compounding with the .model contour a contour havin redetermined characteristics not embodi 1n the model itself.

33. A machine for generatingcams comrising a tool, a work holder and a model bolder, arranged to guide a relative traverse of the tool over the work by means of the model and means for unequally spacing, in a direction transverse to the direction of cam pressure, points on the work reproduced from points equally so spaced in the model.

A machine for making( peripheral cams comprising a tool, a wor holder and a model arranged to guide the tool around the work by means of the model periphery, and mechanism for equally angularl spacing points in the work reproduce from pomts unequally angularly spaced in the model.

35. A cam generatin machine having a model wheel, tool, mo el holder and work holder, means for efl'ecting relative traverses between the said four instrumentalities in pairs whereby a model contour may guide the tool, and mechanism for relativel displacing perpendicularly to the direction of cam action the points on the work piece as compared with the model points from which they were reproduced to form a curve of gradual starting and stopping characterlstics on the work piece.

36. A cam generatin machine having a model wheel, tool, mo e1 holder and work holder, means for effecting relative traverses between the said four instrumentalities in pairs whereb a model contour may guide the tool, an mechanism for comounding with the model contour a contour avin redetermined characteristics not emb ie in the model itself, said mechanism comprising a cam for adding to the normal movement of one of the four firstnamed instrumentalities a component having the characteristicsait is desired to compound with the model contour.

37. A cam generatin machine having a model wheel, tool, mo el holder and work holder, means for effecting relative traverses between the said four instrumentalities in pairs whereby a model contour may guide the tool, and mechanism for compounding with the model contour a contour avin predetermined characteristics not embo ied in the model itself, said mechanism comprising a worm wheel and a worm arranged to slide along the direction of its axis, and a cam having the said characteristics constructed and arranged to slide the worm, and impart the said characteristics to the movement of the worm wheel.

38. A cam model in which the dwells of the cam arerepresented only by isolated points.

39. A cam model in which the dwells of the cam are represented only by isolated Egints and in which the transition curves tween the dwells are represented by curves of substantially uniform rise or fall joining the points.

40. A cam model havin the points corresponding to the cam-dwel accurately plotted on it, said points being joined b curves of substantially uniform rise and fa l.

41. A cam model in which the transition curves betweenthe dwells of the cam are represented b curves of substantially uniformu'ise or all 'oining the portions corre' spggding to the wells.

A cam model consistin of isolated points at generally different distances along the direction in which the cam drives its cooperating member, said points being joined by arcs of circles.

43. A peripheral cam model consisting of isolated points at generally different radial distances from the center, joined by arcs of circles having their centers near the center of the model.

44. A model for a cam generating machine comprising a face plate having means for adjustably attaching separable guides, and separable guides arranged to cooperate with said face plate to form a model periphery and to enga e the model wheel of a cam generatin mac ine.

45. A mode for a cam generating machine comprising a face late having slots, studs adjustable in said s ots, and separable guides connecting said studs to form the model eriphery.

46. model for a cam generating machine com' rising a face plate having radial slots, stu s ad'ustable in said slots, and guides adjusta le with the studs and connecting them two by two to form the model periphery.

47. A model for a cam generating machine comprising a face plate having slots studs adjustable in said slots said studs an face plate being constructed and arranged to cooperate with members of a set of mterchangeable guides to form the model periphery.

48. A model for a cam generating machine comprising a face plate having radial slots, studs adjustable in said slots, and a separable guide constructed and arranged to cooperate with the model wheel and connecting two of said studs to form the model periphery.

49. A model for a cam generating machine comprising a face plate having radial slots, studs adjustable in said slots, and a sector mounted adjustably in the face plate and having a radial slot, whereby said slot may be used in connection with either of the adjoining slots to locate a model are.

50. A model for a cam generating machine consisting of a face plate having scctors relatively angularly adjustable, each of said sectors having a radial slot, studs adjustable in said slots and separable guides connecting said studs to form the model periphery.

51. A model for a cam generating machine consisting of a face plate having sectors relativel argularly adjustable, each of said sectors having means for radial] adjustably attaching a guide constructe and arran ed to act as the model periphery.

52. n a machine of the class described, a model holder, a work holder, :1. model guide and a tool, and means for relatively rotating the model relatively to the guide and the work relatively to the tool, corresponding points of contact on the model and Work being differently angularly spaced.

53. In a machine of the class described, a model holder, a work holder, a model guide and a tool, and means for relatively rotating the model relatively to the guide and the work relatively to the tool, corresponding points of contact on the model and work being difl'erentl angularly spaced, comprising a gearing between the pairs of said relatively rotating instrumentalities.

54. In a machine of the class described, a model holder, at work holder, :1 model guide and a tool, and means for relativel rotating the model relatively to the guide and the work relatively to the tool, correspondin points of contact on the model and work being differently angularly spaced, comprising a gearing for driving the model in definite cycles and a gearing having a member the number of whose teeth is a direct measure of the angular movement of the work corresponding to a cycle of movement of the model.

55. A machine for generating cams comprising a tool, a work holder, and a model holder, arranged to guide a relative traverse of the tool over the work by means of the model and means for circumferentially proportionall spacing, at any desired ratio, points on t e work as regards the corresponding points of the model.

56. A machine for generating cams comprising a tool, a Work holder, and a model holder, arranged to guide a relative traverse of the tool over the work by means of the model, comprising means for rotating the model and work at a constant angmlar velocity ratio, other than unity.

57. A cam generatin machine comprising a model guide an a model consisting of a succession of curves of substantiall uniform rise or fall, a tool and a work hol er, and means for effecting relative circumferential traverses between the members of the said respective pairs of instrumentalities constructed and arranged to reproduce a curve on the model into a curve of differing angular extent in the work.

58. A cam generating machine comprising a model guide and a model consisting of a succession of curves of substantiall uniform rise or fall, a tool and a work holder, and means for effecting relative circumferential traverses between the members of the said respective pairs of instrumentalities constructed and arranged to reproduce a curve on the model into a curve of differing linear extent in the work.

59. A cam generating machine comprising a model wheel and a model having isolated points plotted on it corresponding to the dwells of the cam, and curves of substantially constant rise or fall connecting the said points in order, a tool and a work holder, and means for driving the work holder and model relatively to the tool and model wheel in timed relation with permissive holding of the model wheel on a said point of the model while a corresponding dwell is cut on a work piece held by the work holder.

60. A cam generating machine comprising a model wheel and a model having isolated points ploted on it corresponding to tne dwells of the cam, and curves of substantially constant rise or fall connectin the said points in order, a tool and a wor holder, and means for driving the work holder and model relatively to the tool and model wheel in timed relation with permissive holding of the model wheel on a said point of the model while a corresponding dwell is cut on a work piece held by the work holder, comprising means for feeding the said curves of substantially constant rise or fall over the model wheel at a non-uni form speed to shape transition curves of predetermined characteristics between dwells on the work piece.

61. That improvement in the art of cam generation which consists in accurately plotting points on the model corresponding to the dwells desired in the cam and connecting them by arbitrary curves which are simple considered relatively to the transition curves desired on the work.

62. That improvement in the art of cam generation which consists in accurately plotting points on the model corresponding to the dwells desired in the cam and connect-ing them by arbitrary curves which are simple considered relatively to the transition curves desired on the work, and generating from said arbitrar curves transition curves having desired c aracteristios.

63. That improvement in the art of cam generation which consists in using as a model a curve which is of relatively uniform curvature as regards the cam to be formed, and compounding with the said curve a curve having desired characteristics, as for example, those of easy starting and stopping.

64. That improvement in the art of cam generation which consists in measuring oil the proper distances from the model center to the dwell points, holding the model motionless in the pattern copying machine during the generation of the dwells in the work, and rotating the model from one dwell point to the next to generate the transition curves in the work.

65. A cam model in which the dwells are represented onlyby isolated points and in which the transition curves between the dwells are represented by curves of substantially uniform curvature joining the points.

66. A cam model in which the dwells are represented only by isolated points and in which the transition curves between the dwells are represented by curves of simple character considered relatively to the corresponding portions of the work, joining the points.

67. A cam generating machine comprising model wheel, tool, model holder and work holder, arranged to guide the tool around the model peripher by the contact of the model wheel and in el, and a control for compounding with the model periphery a curve of predetermined characteristics.

68. A cam generating machine comprising model wheel, tool, model holder and work holder, arranged to guide the tool around the model periphery by the contact of the model wheel and model and a control comprising a variable rotation device for compounding with the model periphery a curve of predetermined characteristics.

69. A cam generating machine comprising model wheel, tool, model holder and work holder, arranged to guide the tool around the model periphery by the contact of the model wheel and model, and a control for deforming the model periphery in the work to produce characteristics not present in the model peripher 70. In a mac ine of the class described, a model wheel and tool, a model holder and work holder, and mechanism for effecting movement of the model wheel relatively to the model holder and of the tool relatively to the'work, one of said movements being intermittent, but of the same average velocity as the other.

71. In a machine of the class described, a model wheel and tool, a model holder and work holder and mechanism for effecting movement of the model wheel relatively to the model holder and of the tool relatively to the Work, said movements occurring in cycles, those of successive cycles having different relative angular velocities. I

In testimony whereof I have signed my name to this specification.

LAURENCE E. TOPHAM.

63. That improvement in the art of cam generation which consists in using as a model a curve which is of relatively uniform curvature as regards the cam to be formed, and oompoundin with the said curve a curve having desired characteristics, as for example, those of easy starting and stopping.

64. That improvement in the art of cam generation which consists in measuring oil the proper distances from the model center to the dwell points, holding the model motionless in the pattern copying machine during the generation of the dwells in the work, and rotating the model from one dwell point to the next to generate the transition curves in the work.

65. A cam model in which the dwells are re resented only by isolated points and in w ich the transition curves between the dwells are represented by curves of substantially uniform curvature joining the points.

66. A cam model in which the dwells are represented only by isolated points and in which the transition curves between the dwells are represented by curves of simple character considered relatively to the corresponding portions of the work, joining the points.

67. A cam generating machine comprising model wheel, tool, model holder and work holder, arranged to guide the tool around the model periphery by the contact of the model wheel and model, and a control for compounding with the model periphery a curve of predetermined characteristics.

68. A cam generating machine comprising model wheel, tool, model holder and work holder, arranged to guide the tool around the model periphery by the contact of the model wheel and model and a control comprising a variable rotation device for compounding with the model periphery a curve of predetermined characteristics.

69. A cam generating machine comprising model Wheel, tool, model holder and work holder, arranged to guide the tool around the model periphery by the contact of the model wheel and model, and a control for deforming the model periphery in the work to produce characteristics not present in the model peripher 70. In a machine of the class described, a model wheel and tool, a model holder and work holder, and mechanism for effecting movement of the model wheel relatively to the model holder and of the tool relatively to the work, one of said movements being intermittent, but of the same average velocity as the other.

71. In a machine of the class described, a model wheel and tool, a model holder and work holder, and mechanism for effecting movement of the model wheel relatively to the model holder and of the tool relatively to the work, said movements occurring in cycles, those of successive cycles having different relative angular velocities.

In testimony whereof I have signed my name to this specification.

LAURENCE E. TOPHAM.

CERTIFICATE OF CORRECTION.

Patent No. l, 597, 741.

LAURENCE E.

Granted August 31, 1926, to

TOPHAM.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 16, strike out the word "and" and insert the same after "1923," in line 20; page 3, line 17, for the misspelled word "inprotant" read "important"; page 4, line 43. for

the word "is" read "in", and line 113, for the word "came" read "cam"; page 5.

line 40, after the word "reduced" insert a coma; same page, line 63, after the article "the" insert the word "hollow"; page 6, line 23, strike out the words "drop in the"; page 10, line 16, claim 51, for the misspelled word "argnlarly" read "angnlarly", and line 99, claim 60, for the word "ploted" read "plotted";

and that the said Letters Patent should he read with these corrections therein that the cape may conform to the record of the case in the Patent Office.

Signed and sealed-this 28th day of June, A. D. 1927.

Sea].

M. J. MOORE. Acting Conmlssioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,597,741. Granted August 31, 1926, to

LAURENCE E. TOPHAM.

[t is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1. line 16, strike out the word "and" and inaert the same after "1923," in line 20; page 3, line 17, for the misspelled word "improtant" read "important"; page 4, line 43. for the word "is" read "in", and line 113, for the word "came" read "cam"; page 5, line 40, after the word "reduced" insert a comma; same page, line 63, after the article "the" insert the word "hollow"; page 6, line 23, strike out the words "drop in the"; page 10, line l6, claim 51, for the misspelled word "argularly" reed "ang'ularly", and line 99, claim 60, for the word "ploted" read "plotted"; and that the said Letters Patent ahonld be read with these corrections therein that the may conform to the record of the case in the Patent Office.

Signed and aealedthia 28th day of June, A. D. 1927.

M. J. MOORE. Seal. Acting Commissioner of Patents. 

